The present invention relates to static dissipative electrical cables, and more particularly relate to electronic equipment signal cables which dissipate triboelectric charge.
It has been discovered that computer systems are very sensitive to static electricity or triboelectric charging on signal cables which can cause errors and system disruptions. These system disruptions are very undesirable in those systems wherein field system up-grades are being performed while keeping the system on-line and in large multiprocessing systems designed for continuous operation through parallel maintenance. It has been determined that standard high speed tri-lead logic cables show several hundred to several thousand volts residing on the cable jacket, which could persist for weeks on the cable while in the machine environment. Abrupt discharging of such voltages could cause system level disruptions.
Attempts in the past to discharge triboelectric charges on the cables has included the use of grounding straps on personnel handling the cables, or on the cables themselves. However, the grounding straps discharge only the spot on the cable they touch, and do not discharge voltages caused by triboelectric charging even a short distance away. Air ionizers have also been used in an attempt to dissipate triboelectric charges on the cables.
U.S. Pat. No. 4,498,116 issued Feb. 5, 1985 to Saurenman for Control of Static Neutralization Employing Positive and Negative ION Distributor discloses an apparatus to reduce static electricity in a work zone.
U.S. Pat. No. 4,422,483 issued Dec. 27, 1983 to Zins for Antistatic Fabric and Garment Made Therefrom discloses a garment for use in "clean rooms" in which conductive filaments in the fabric provide anti-static properties.
U.S. Pat. No. 4,196,464 issued Apr. 1, 1990 to Russell for Semi-Conductive Layer-Containing Reinforced Pressure Hose and Method of Making Same, and Canadian Patent No. 1051793 issued Apr. 3, 1979 to Johansen for Composite Paint Hose, both of which disclose hoses for conveying paint and include an electrically semi-conductive layer which serves as a ground for static electricity.